supabase-admin

Supabase Administration Expert

Master Supabase schema design, Row Level Security policies, migrations, and performance optimization for production applications.

When to Use

✅ USE this skill for:

• Row Level Security (RLS) policy design and debugging
• Database migrations and schema changes
• Auth integration (triggers, profile creation)
• Query performance optimization
• Supabase-specific SQL patterns (auth.uid(), auth.jwt())

❌ DO NOT use for:

• Supabase Auth UI configuration → use Supabase dashboard docs
• Edge Functions → use cloudflare-worker-dev skill
• General PostgreSQL without Supabase context → use standard SQL resources
• Client-side Supabase SDK usage → use Supabase JS docs

Core Competencies

1. Row Level Security (RLS)

Always Enable RLS on User Tables:

ALTER TABLE your_table ENABLE ROW LEVEL SECURITY;

Policy Patterns:

-- Public read, authenticated write
CREATE POLICY "Public read" ON posts FOR SELECT USING (true);
CREATE POLICY "Owners can write" ON posts FOR INSERT
  WITH CHECK (auth.uid() = user_id);

-- Owner-only access
CREATE POLICY "Users own their data" ON profiles
  FOR ALL USING (auth.uid() = id);

-- Role-based access
CREATE POLICY "Admins can do anything" ON content
  FOR ALL USING (
    EXISTS (
      SELECT 1 FROM profiles
      WHERE profiles.id = auth.uid()
      AND profiles.role = 'admin'
    )
  );

Performance-Critical: Index auth.uid() Columns:

-- 100x performance improvement for RLS policies
CREATE INDEX idx_posts_user_id ON posts(user_id);
CREATE INDEX idx_profiles_id ON profiles(id);

Subquery Optimization for JWT Functions:

-- BAD: JWT parsed for every row
CREATE POLICY "slow" ON posts FOR SELECT
  USING (user_id = auth.uid());

-- GOOD: JWT parsed once via subquery
CREATE POLICY "fast" ON posts FOR SELECT
  USING (user_id = (SELECT auth.uid()));

2. Migration Best Practices

File Naming Convention:

supabase/migrations/
├── 001_initial_schema.sql
├── 002_add_profiles_trigger.sql
├── 003_forum_tables.sql
└── 004_add_rls_policies.sql